1. Field of the Invention
The present invention relates to a line driver circuit, and to an electro-optic device and a display device using the same.
2. Description of the Related Art
Display panels, such as liquid crystal displays, are used as display units in electronic devices, such as cell phones for example, in an effort to achieve low power consumption and reduce the size and weight of the electronic devices. Since delivering video and still images with high content value has become possible with the rapid spread and acceptance of cell phones in recent years, high image quality has also become necessary for display panels in cell phones, and other devices used to deliver video/image contents.
Active matrix liquid crystal panels using thin film transistor (“TFT” below) liquid crystals are known as one type of liquid crystal panel achieving high image quality in the display unit of such electronic devices. Organic EL panels using organic EL elements are another type.
In an active matrix liquid crystal panel using TFT liquid crystals, for example, a high voltage is required for driving the display the value of the high voltage being dependent upon the liquid crystal material and TFT transistor capacity. As a result, the driver circuit (line driver circuit) and power supply circuit for driving an active matrix, LCD panel display, must be manufactured using a high breakdown voltage process.
There is therefore a problem that even as device geometry processes continues to get smaller, the benefits of low cost offered by reduced dimensions cannot be realized in LCD panel drivers.
Furthermore, advances in packaging technology and communication technology have led to rapid acceptance of cell phones and other such mobile communication devices, and communication service providers are improving communication services in an attempt to obtain new users. It is therefore essential for cell phone manufacturers to quickly bring to market products compatible with the various communication services. To achieve this, it is essential for the manufacturer to shorten the product development TAT.
Using cell phones by way of example, the arrangement of semiconductor devices for driving the display panel of the cell phone's display unit differs according to the packaging method. Additionally, the display control timing can change due to specification changes during development. In such cases product redesign becomes a cause for delayed market introduction. Therefore, being able to shorten the development TAT to allow for product design flexibility is desirable even in the above case.